System for displaying esophageal function

ABSTRACT

A system for displaying an esophageal operation includes a display device, an interface capable of receiving esophageal impedance and pressure measurements, and a processing system in communication with the display device, the interface, and an esophageal operation model. The processing system is configured to receive a plurality of impedance values from a first plurality of spaced-apart esophageal locations, receive a plurality of pressure values from a second plurality of spaced-apart esophageal locations, process the plurality of impedance values and the plurality of pressure values with the esophageal operation model, display the plurality of impedance values on the display device as a bolus transit, and display the plurality of pressure values on the display device as operational esophagus movement.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a divisional of U.S. patent application Ser.No. 10/935,898, filed on Sep. 7, 2004, and also claims the benefit ofU.S. Provisional Patent Application 60/500,486 entitled “EsophagealFunction Display And Playback System And Method For DisplayingEsophageal Function”, filed Sep. 5, 2003, by Thomas D. Stuebe, U.S.Provisional Patent Application 60/500,555 entitled “Esophageal WaveformAnalysis for Detection and Quantification of Reflux Episodes”, filedSep. 5, 2003, by Thomas D. Stuebe, and U.S. Provisional Application60/554,794 entitled “Intraluminal Impedance: Electromagnetic Modeling,Signal Analysis, and Computer-Assisted Diagnosis of GastroesophagealReflux”, filed Mar. 19, 2004, by Awad Al-Zaben, VenkatachalamChandrasekar, and Thomas D. Stuebe, and the entire contents of saidapplications are hereby specifically incorporated by reference hereinfor all they disclose and teach.

FIELD OF THE INVENTION

The present invention relates generally to medical display systems andmore particularly to the display of esophageal functions.

BACKGROUND OF THE INVENTION

Gastrointestinal reflux is the travel of liquids, including stomachacids, up the esophagus. The esophagus normally functions to transportfood and liquids down to the stomach during a swallow. During a swallow,a peristaltic wave (i.e., a contraction of the muscles of the esophagus)moves progressively downwardly in the esophagus and pushes the fooddownwardly during a swallow. In addition, a normal swallowing operationincludes a coordinated opening and closing of the Lower EsophagealSphincter (LES). The LES normally prevents the contents of the stomachfrom coming back up the esophagus. Therefore, in a normal swallow, theesophageal muscles and the LES work in conjunction to transport a bolusof liquid or food to the stomach and prevent any retrograde travel ofthe bolus in an opposite direction.

Gastrointestinal reflux, or GastroEsophageal Reflux Disease (GERD), isan abnormal esophageal operation in which a portion of the stomachcontents (i.e., a bolus) passes through the LES and travels at leastpartly back up the esophagus in a retrograde motion. In persons withgastrointestinal reflux, the LES muscle commonly is either weak orrelaxes inappropriately with exposure to fatty and spicy foods, certaintypes of medications, tight clothing, smoking, alcohol consumption,vigorous exercise, or changes in body position. The reflux can causeproblems such as heartburn-like pain symptoms, chest pain similar tocardiac problems, aggravated asthma symptoms, hoarseness, sinusproblems, snoring problems, and other respiratory problems. Severe orprolonged acid reflux can cause inflammation (esophagitis) and canultimately damage the lining of the esophagus. Reflux is usually notnoticeable or harmful during the day since the esophagus is protectedduring waking hours by swallowing, by the flow of saliva, and by gravity(assuming the sufferer is standing or sitting up). However, at night,these protective mechanisms are less effective. Consequently, nighttimeacid reflux is more likely to remain in the esophagus longer and cancause greater damage.

A normal course of treatment for non-critical reflux is typically theadministration of acid-reducing or acid-blocking medications. However,serious and/or long-term gastrointestinal reflux can often necessitatesurgery on the LES or on the stomach. Therefore, it is desirable in allcases to be able to detect, measure and diagnose any abnormal operationsof the esophagus in order to prevent or treat the reflux.

The occurrence of gastrointestinal reflux has previously been detectedby inserting a probe into the esophagus of a subject and measuring acidor pH levels. Therefore, reflux was detected by simply detecting thepresence of acid. The drawback of this approach is that it does not showthe operational dynamics of the esophagus, i.e., it does not show musclemovement or LES operation, and cannot determine the underlying cause ofthe reflux. In addition, this approach may not be able to continuouslymeasure acid levels in a patient over a significant period of time.Furthermore, such an approach may not show the extent of refluxoccurrence, since this approach is incapable of detecting the reflux ofrelatively non-acidic stomach fluids.

Esophageal measurements have typically been presented as raw numbers orline graphs that show values taken over time. Therefore, doctors ormedical personnel have to interpret the data in order to obtainmeaningful information. For example, the reviewer may have to correlatea swallow operation with a feature of a line graph. This is difficultand time consuming. It is even more difficult if the person analyzingthe data has to correlate multiple data readings for the patient.Moreover, in order to detect reflux or other swallowing abnormalities,the subject may have to wear a monitoring device that measures andgathers data over hours or even days. Therefore, the reviewer may haveto review and assess a tremendous quantity of data. This leads toinefficiency since a large amount of time is spent in analyzing data.Furthermore, the accuracy of the results can be easily degraded as aconsequence of human error in reading, processing, and analyzing thelarge amounts of data. Also, these large amounts of time increase thecost to the patient in performing these tests.

SUMMARY OF THE INVENTION

The present invention overcomes the disadvantages and limitations of theprior art by providing a system and method for displaying esophagealoperation of a subject. The esophageal operation display systemcomprises a display device, an interface capable of receiving esophagealimpedance and pressure measurements, and a processing system incommunication with the display device, the interface, and an esophagealoperation model. The processing system is configured to receive aplurality of impedance values from a first plurality of spaced-apartesophageal locations, receive a plurality of pressure values from asecond plurality of spaced-apart esophageal locations, process theplurality of impedance values and the plurality of pressure values withan esophageal operation model, display the plurality of impedance valueson the display device as a bolus transit, and display the plurality ofpressure values on the display device as operational esophagus movement.

A method of displaying esophageal operation is also disclosed accordingto an embodiment of the invention. The method comprises receiving aplurality of impedance values from a first plurality of spaced-apartesophageal locations, receiving a plurality of pressure values from asecond plurality of spaced-apart esophageal locations, processing theplurality of impedance values and the plurality of pressure values withan esophageal operation model, displaying the plurality of impedancevalues as a bolus transit, and displaying the plurality of pressurevalues as operational esophagus movement.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows an embodiment of an esophageal operation display system.

FIG. 2 is a flowchart of a method of displaying esophageal operationaccording to an embodiment of the invention.

FIG. 3 shows a graph of measured impedance values versus time.

FIG. 4 shows an esophageal operation display screen according to anembodiment of the invention.

FIGS. 5A-5E illustrate a normal swallow sequence as shown on an animateddisplay portion of the esophageal operation display system.

FIGS. 6A-6E illustrate an abnormal swallow sequence as shown on theanimated display portion.

DETAILED DESCRIPTION

FIG. 1 shows one embodiment of an esophageal operation display system100. The system 100 includes a processing system 120, a display device130, and an optional user input device 124. The processing system 120communicates with an esophageal probe 110 and receives impedance andpressure values measured by the esophageal probe 110. In addition, theprocessing system 120 communicates with the display device 130 and theuser input device 124.

The processing system 120 can comprise any desired processing device andincludes an interface 123 and a storage system 121 that stores digitaldata. The processing system 120 receives impedance and pressure valuesthrough the interface 123. The storage system 121 stores receivedimpedance and pressure values, and stores other data, including analysisresults for impedance and pressure data. In addition, an esophagealoperation model 122 is stored in the storage system 121 and is accessedby the processing system 120.

The user input device 124 is in communication with the processing system120. Through the user input device 124, an operator can initiate andcontrol the analysis of impedance and pressure values and can controlthe display of esophageal operation results. The user input device 124can comprise an integral component or can comprise an external devicecapable of sending inputs and commands to the processing system 120. Forexample, the user input device 124 can comprise a keyboard or keypad, amouse, joystick, or other pointing device. Alternatively, the user inputdevice 124 can comprise a general purpose computer configured as acontroller, a specialized controller device, an analyzer, a basestation, etc. The user input device 124 can also comprise a remotedevice. The processing system 100 may receive commands from the userinput device 124 over a computer network, such as a local area network(LAN), a wide-area network (WAN), the Internet, wirelessly, etc.

The display device 130 can be any type of computer screen or display. Itshould be understood that the display device 130 may be a component ofthe processing system 120, or may be a separate device, as in the userinput device 124 above. In one embodiment, the processing system 120 isconnected to the display device 130 and the user input device 124, by awire, cable, fiber/optical fiber, etc. In another embodiment, theprocessing system 120 communicates wirelessly with the display device130 and the user input device 124, such as through radio frequency (RF)communications, infrared (IR) communications, ultrasonic communications,etc. It should be understood that the display device 130 and the userinput device 124 can comprise an integrated user interface, and cancomprise a remote computer device that is in communication with theprocessing system 120, such as through a modem, network card, or othercommunication interface device (not shown).

In operation, the processing system 120 receives impedance and pressurevalues, stores the values in the storage system 121 if needed, andaccesses the esophageal operation model 122 in order to process thereceived pressure and impedance values and generate display data. Theprocessing system 120 can receive the impedance and pressure values fromthe esophageal probe 110, or can receive them from other sources, suchas from a storage device or external computer device. The esophagealoperation model 122 generates display data from the impedance andpressure values in accordance with processes known to those skilled inthe art. The display data can be in a conventional display format, suchas an MPEG or other image format, etc. The display data is thenprocessed by processing system 120 and transmitted to and displayed onthe display device 130. In addition, the display data can be stored forlater use and can be transmitted to other devices. This can enablemedical personnel to transfer a patient's data to another person forconsultation, etc.

The display of esophageal operation shows a gastroesophageal refluxoccurrence, but cannot be identified as acidic unless pH (acidity)measurements are also performed in the esophagus of the subject. Toprovide direct measurements of the pH values, pH sensors can be added tothe probe, as described below. The system and method of the inventionwill typically be employed when gastroesophageal reflux has beendiagnosed, and can advantageously be used to determined the underlyinggastroesophageal mechanism responsible for the reflux.

The esophageal operation model 122 describes average or typicalcharacteristics of a human esophagus (or any other animal having anesophagus). The esophageal operation model 122 may include data on, forexample, typical esophagus diameter, typical bolus impedances, airimpedance, expected food impedances, typical peristaltic pressure,typical resting pressure of the Lower Esophageal Sphincter (LES),typical LES swallowing pressure, correlation of a LES pressure to a LESopening amount, pH, etc. This data is used by the processing system 120to interpret the received pressure and impedance values, and can befurther used to model a peristaltic wave, to model a LES opening andclosing operation, to model a bolus transit, etc. Modification of thedata and modeling of esophageal operation may employ the processesdisclosed in the above referenced applications. Therefore, when theprocessing system 120 processes the impedance and pressure values withthe esophageal operation model 122, the processing system 120 can createthe display data that represents the esophageal operation.

The esophageal probe 110 can comprise a combined impedance catheter andmanometry (pressure) catheter, or can comprise separate impedance andmanometry catheters. The esophageal probe 110 can be substantiallyflexible or partially rigid, and can include markings or indicia thatguide the insertion and the insertion depth of the esophageal probe 110.It should be understood that the drawing is not to scale. The esophagealprobe 110 can include pressure sensors 111 a-111 e that measure pressurevalues in the esophagus and impedance sensors 112 a-112 d that measureimpedance values. When the esophageal probe 110 is in position, thebottom pressure sensor 111 e should be located substantially in the LES102.

The esophageal probe 110 can be directly connected to the interface 123of the processing system 120, such as by a wire 119, cable 119,fiber/optical fiber 119, etc. Alternatively, the esophageal probe caninclude a probe interface (not shown) that is not directly connected tothe processing system 120, but can communicate with the processingsystem 120. In one embodiment, the probe interface communicates with theprocessing system 120 in a wireless manner, such as through a RF link,an IR link, an ultrasonic link, etc. In another embodiment, the probeinterface can include a removable storage medium, such as an optical,magnetic, or solid state storage device, that can store probemeasurements and can be transferred to the interface 123 of theprocessing system 120, where the stored values are downloaded.

It can be seen that the various pressure and impedance sensors arespaced along the length of the esophageal probe 110 in order to obtainimpedance and pressure measurements in a variety of spaced apartlocations in the esophagus. For example, in the embodiment shown, thebottom pair of impedance sensors 112 d and the pressure sensor 111 d arelocated about 5 centimeters up from the bottom pressure sensor 111 e.The second set of impedance sensors 112 c and the pressure sensor 111 care located about 10 centimeters up from the bottom sensor 111 e, thethird set of impedance sensors 112 b and the pressure sensor 111 b arelocated about 15 centimeters up from the bottom sensor, and the fourthset of impedance sensors 112 a and the pressure sensor 111 a are locatedabout 20 centimeters up from the bottom sensor.

It should be understood that different spacings may be used anddifferent numbers of impedance and pressure sensors may be used, asdesired. The sensors are spaced apart in order to track a peristalticwave and track a bolus transit through the esophagus. It should beunderstood that more sensors spaced closer together could provide ahigher degree of resolution, if needed.

The impedance sensors 112 a-112 d comprise conductive portions, such asmetallic rings or ring portions. A very small electrical current istransmitted from one contact of an impedance sensor pair and received atthe other contact. For example, the top two conductive strips 112 a canmeasure an electrical impedance therebetween by transmitting andreceiving a small electrical current. However, each impedance sensorpair must be spaced far enough from the other impedance sensors so thatthe sensors do not receive any stray electrical current from othersensor pairs.

The ratio of voltage to an alternating current for a particularfrequency is a measure of the impedance. In practice, impedance isobtained by applying a very small voltage between adjacent contacts ofthe sensor pair and measuring the resulting electrical current. Thehighest electrical current flows when there is a bolus present.Impedance is therefore a measure of the specific conductivity of anymaterial adjacent to and in contact with the impedance sensor pairs.Impedance can also provide an indication of the amount of material ofthe bolus. In one embodiment, the excitation current present between anytwo impedance sensor contacts is passively limited to less than 8microamperes, with a frequency of between one and two kilohertz. Othervalues can be used, depending on the material of the bolus, and theprevious values are given merely for purposes of illustration. Anexcitation current of 8 microamperes is three orders of magnitude belowthe threshold of cardiac stimulation for a one-kilogram body, andprovides an injected power of about 0.00025 microwatts. In oneembodiment, the excitation current path is constrained to terminate onan electrode pair by a transformer, and there is no possible currentpath through other organs.

Impedance measurements provide a method for the detection of the bolushead and the bolus tail based upon the response of the impedance signal(see FIG. 3). The impedance values can be used to make severaldeterminations. The impedance values can be used to determine the amountof time that a bolus is present in the esophagus, including the amountof time the bolus is present at each respective level of the esophagus.In addition, the impedance values can be used to determine a bolustransit time, i.e., an amount of time from bolus entry into the proximalesophagus (about 19 centimeters above the LES 102 in a typical person)to bolus exit in the distal esophagus (about 5 centimeters above the LES102). Furthermore, the impedance values can be used to determine bolustransit effectiveness, i.e., a determination of the ability of theesophagus to achieve bolus transit for each respective test swallow.

The pressure sensors 111 a-111 e comprise any suitable pressure sensors,such as described in the above referenced applications. The pressurevalues measured by the pressure sensors 111 a-111 d may be measured as aresult of a bolus traveling through the esophagus. The pressure valuemeasured by the bottom pressure sensor 111 e reflects a pressure exertedby the LES 102.

It should be noted that pressure sensors 111 d and 111 e may physicallydiffer from pressure sensors 111 a-111 c. The larger size of the bottompressure sensor 111 e will better accommodate the need to capture LESreadings and will accommodate some variance in placement of the probe110 (i.e., each subject may have a different length esophagus). Thelarger size of the pressure sensor 111 d allow pressure sensor 111 d toobtain a more accurate reading in the esophagus near the LES 102, due tothe higher likelihood of reflux in this region. In one embodiment, thepressure sensors 111 d-111 e may be circumferential sensors that measurepressure on the circumference of the esophageal probe 110, while thepressure sensors 111 a-111 c can comprise spot sensors that measurepressure at a specific region of the esophageal probe 110, such as apressure sensor having a circular face.

FIG. 2 is a flowchart 200 of a method of displaying esophageal operationaccording to an embodiment of the invention. In step 201, the processingsystem 120 receives a plurality of impedance values, such as a set oftime-sampled impedance values from a plurality of spaced-apartesophageal locations. In one embodiment, the plurality of impedancevalues are received from the esophageal probe 110. The impedance valuescan be accumulated, stored, recalled, etc., as disclosed above.

In step 202, the processing system 120 receives a plurality of pressurevalues, such as a set of time-sampled pressure values from a pluralityof spaced-apart esophageal locations. The plurality of pressure valuescan be received directly from the esophageal probe 110 or retrieved fromstorage for processing and display. The pressure values can be stored,accumulated, processed, recalled, etc. for subsequent display on thedisplay device, or the processed data can be stored for subsequentdisplay on the display device. In one embodiment the spaced-apartlocations of the impedance and pressure values are substantially thesame, although in other embodiments, the pressure and impedance valuescould be obtained at different, non-corresponding locations in theesophagus.

The impedance and pressure values are typically received from theesophageal probe 110 during or after a measurement session. Theprocessing system 120 can accumulate the values. The measurement sessioncan include specific swallowing and postural procedures performed by thetest subject, including swallowing a test bolus of a fluid having knownand controlled properties (such as viscosity). The test bolus maytherefore exercise the dynamic muscular operation of the esophagus. Themeasurement session can be conducted in order to ascertain peristalticwave strength, peristaltic wave speed/contraction timing, bolus transiteffectiveness, and bolus transit timing. The subject's performance canbe analyzed and compared to normal values in order to determine adisease state and to plan any indicated therapy.

In step 203, the processing system 120 processes the impedance andpressure values with the esophageal operation model 122, as previouslydiscussed. The processing is performed in order to generate display datarepresentative of the esophageal operation.

In step 204, the processed impedance values are displayed on a graphicaldisplay, such as on the display device 130. The processed impedancevalues represent the location and the movement of a bolus (i.e., a bolustransit). In addition, the processed impedance values can be usedwhether the bolus comprises water, acid, food or food liquids, or evenair.

In step 205, the processed pressure values are displayed as operationalesophagus movement. For example, the processed pressure values canrepresent a peristaltic wave and opening and/or closing of the LES 102.Therefore, the processed pressure values are displayed as muscularmovements within the esophagus. The pressure values can be used todetermine proper peristaltic wave behavior. For example, if thecontraction pressure of the peristaltic wave is greater than or equal toabout 30 mmHg and the speed of the wave is about 8.0 centimeters persecond, the doctor may determine that the peristalsis was effective.

FIG. 3 shows a graph of measured impedance values versus time. The graphshows how the impedance values may vary during transit of a bolus. Forexample, if the bolus is a fluid, the measured impedance will normallydrop due to the presence of the water around the impedance probe 110,and consequently the bolus can be detected over time by the trough ofimpedance values. In addition, the chart may be used to determine abolus exit from the esophagus (if there is one).

FIG. 4 shows an esophageal operation display screen 400 according to anembodiment of this invention. The screen 400 comprises display data thatis viewed on the display device 130 (see FIG. 1). The screen 400includes a data display portion 402 and an animated display portion 404.It can be seen from FIG. 4 that multiple time-sampled impedance values(i.e., impedance traces 420) and multiple time-sampled pressure values(i.e., pressure traces 422) are simultaneously displayed. It should beunderstood that the data and animated displays can be provided in otherformats and can include different user interface icons, buttons, textand/or labels, etc. Through use of the screen 400, the inventionadvantageously provides a visual representation of both the bolustransit and the esophageal operation.

The data display portion 402 can include the display of a line graph foreach impedance and pressure sensor of the esophageal probe 110. The linegraphs show measured esophageal values over a window of time. The datadisplay portion 402 can include impedance traces 420 (displayed in termsof impedance Z in units of ohms) and pressure traces 422 (in units ofmillimeters of mercury, or mmHg). In one embodiment, a user can select atime window (such as a time window for viewing in the animated displayportion 404, using the vertical window control boundaries 430), canselect time scales, can move chronologically forward or backward throughthe displayed data, can start and stop a motion of the graphs over time,can halt the graphs at a particular point in time (such as if the userspots an anomaly in the data), can zoom in or out, can select verticaldisplay scaling, can select sensors to be displayed (i.e., the user canadd or remove certain sensor values), etc. All of these functions arecapable of being provided by those skilled in the art of displaytechnology.

The animated display portion 404 can be animation drawings or otherrepresentation of esophageal operation. The animated display portion 404represents pressure values as esophageal muscle action and representsimpedance values as bolus transit. It should be noted that the animateddisplay of the bolus does not necessarily represent an actual bolusvolume. The animated display portion 404 can include a proberepresentation 406 of the esophageal probe 110, including depicting theimpedance and pressure sensor locations. The animated display portion404 can include a black-and-white, grayscale, or color animation. Theanimated display portion 404 can additionally display the acidity of thebolus, such as by using a color scale, if acidity measurements from pHsensors on the probe 110 are received along with the impedance andpressure values.

The animated display portion 404 can be displayed in real time or can bedisplayed according to a user-selected time scale. For example, the usercan control the animation using the start/end and slow/fast controls431. The user can further use the playback controls 432 to control theanimated display portion 404. Consequently, this invention enables theuser to sift through large amounts of data very quickly and efficientlyand to look for specific actions of the esophagus, and it can repeatedlyloop through a specific portion of data for repetitive viewing by theuser. In this manner, the user can look for certain abnormalitiesvisually, such as the peristaltic wave 410 passing the bolus 408, theLES 412 not returning to a closed position after a bolus transit, theLES 412 not returning to a closed position within a certain amount oftime, movement of the LES 412 without an accompanying peristaltic waveand/or bolus, etc.

The animated display portion 404 advantageously allows a doctor, amedical technician, and/or the patient to view and understand theoperation of a particular patient's esophagus, and further enablesefficient and intuitive understanding of any abnormal esophagealoperation by visual observation. For example, the viewer can observe aperistaltic wave 410 in conjunction with the opening/closing of the LES412. The user can see the peristaltic wave 410 move down the esophagusand can see the bolus 408 in relation to the peristaltic wave 410. Inaddition, the viewer can observe the opening and closing of the LES 412in relation to both the peristaltic wave 410 and the transit of thebolus 408.

The advantages of the animated display portion 404 are further evidentwhen compared to the data display portion 402. The series of line graphsof the data display portion 402, although they contain the sameinformation as the animated display portion 404, are more difficult tointerpret, even for trained medical personnel, than the animated display404. For example, the peaks and valleys in the various line graphs arehard to relate to an actual physical function of the esophagus, whereasthe animated display 404 shows such physical functions visually. Inaddition, without the animated display 404, the viewer must mentallycorrelate the pressure and impedance values and how these valuesrepresent esophageal physical movements, functions, and abnormalities.Moreover, the animated display 404 may help the user to detect importantesophageal abnormalities that may otherwise be missed by the user,especially in light of the amount of data, which is typically obtainedover a long study period, for example, 24 hours. Hence, the animateddisplay helps the person analyzing the data to view a visualrepresentation of the data, which allows large amounts of data to beanalyzed in a quick and easy manner.

FIGS. 5A-5E illustrate a normal swallow sequence as shown on theanimated display portion 404 of the esophageal operation display system100. FIG. 5A depicts the esophagus at rest, wherein the LES 412 isbasically closed and the rest of the esophagus is relaxed. FIG. 5B showsthe LES 412 starting to open and also shows the presence of the bolus408 in the esophagus. FIG. 5C shows the esophagus when the bolus 408 hasmoved closer to the LES 412, and further shows the peristaltic wave 410following the bolus 408. This is expected and normal esophagealoperation, wherein the peristaltic wave 410 (i.e., the ripplingcontraction of the esophageal muscles) follows the bolus 408 and forcesit down the esophagus. FIG. 5D shows the bolus 408 passing through theopen LES 412, with the peristaltic wave 410 immediately behind it. FIG.5E shows the esophagus after the bolus 408 has passed into the stomachand the LES 412 has returned to a closed position. The peristaltic wave410 has terminated, and thus cannot be seen in FIG. 5E.

FIGS. 6A-6E illustrate an abnormal swallow sequence as shown on theanimated display portion 404. It should be understood that there areother types of abnormal swallow sequences, and this sequence shows justone mechanism. Other mechanisms may likewise be shown and depicted bythe invention. FIG. 6A again shows the esophagus at rest, with the LES412 being closed. FIG. 6B again shows the bolus 408 approaching the LES412, which is starting to open. FIG. 6C again shows the bolus 408approaching the LES 412 followed by the peristaltic wave 410. FIG. 6Dshows a deviation wherein the LES 412 has not fully opened, andconsequently the peristaltic wave 410 passes the bolus 408. As a result,in FIG. 6E the bolus 408 has not passed through the LES 412 and is stillwithin the esophagus, even though the peristaltic wave 410 hasterminated. Therefore, in this example, the swallowing is abnormal andhas not successfully completed.

It should be understood that an abnormal swallow sequence may includeother problems. For example, an abnormal swallow sequence may beindicated by an incomplete opening of the LES 412, a poor or ineffectiveperistaltic wave 410, or a failure of the LES 412 to fully close(wherein a bolus actually emerges from the stomach and moves upward in aretrograde motion and is not contained by the LES 412).

The invention provides a graphical representation of esophageal functionand provides a two-dimensional animated representation of dynamicesophageal operational. The invention also provides swallow and refluxdata in real time, allowing changes to the time scale, stopping andstarting of the display of esophageal operation, and the ability tofocus on critical swallowing operations.

The invention provides several benefits. The invention enables pressureand impedance values to be processed and displayed together in order topresent an accurate and life-like model of swallowing operations. Theinvention provides an improved and easily used display of esophagealdata, including data that allows medical personnel to fully understandnormal and abnormal esophageal operation. The invention providesbenefits in training of medical personnel. The invention allows medicalpersonnel to accurately assess and diagnose swallowing abnormalitieswhile reducing data processing and analysis time. The invention can beutilized to efficiently determine a course of treatment for a patient.In addition, the invention enables display of patients'problems/symptoms in order to show the existence of a swallowingabnormality and to explain a swallowing and/or reflux problem. Moreover,a dynamic playback of bolus transit is achieved without use of aradiation scan, with its attendant cost and risk drawbacks.

The foregoing description of the invention has been presented forpurposes of illustration and description. It is not intended to beexhaustive or to limit the invention to the precise form disclosed, andother modifications and variations may be possible in light of the aboveteachings. The embodiment was chosen and described in order to bestexplain the principles of the invention and its practical application tothereby enable others skilled in the art to best utilize the inventionin various embodiments and various modifications as are suited to theparticular use contemplated. It is intended that the appended claims beconstrued to include other alternative embodiments of the inventionexcept insofar as limited by the prior art.

1. A system for displaying a representation of esophageal operation of asubject comprising: a display device; an interface capable of receivingesophageal impedance and pressure measurements; and a processing systemin communication with said display device, said interface, and anesophageal operation model, with said processing system configured toreceive a plurality of impedance values detected at a first plurality ofspaced-apart esophageal locations, receive a plurality of pressurevalues detected at a second plurality of spaced-apart esophageallocations, process said plurality of impedance values and said pluralityof pressure values with said esophageal operation model, generatedisplay data that is a representation of a bolus transit from saidplurality of impedance values, and generate display data that is arepresentation of esophageal movement from said plurality of pressurevalues.
 2. The system of claim 1 further comprising a user input devicein communication with said processing system, said user input devicecapable of accepting user inputs and transferring said user inputs tosaid processing system.
 3. The system of claim 1 wherein said interfacecomprises a wireless interface that communicates wirelessly with anesophageal probe.
 4. The system of claim 1 further comprising anelectrical connector that directly connects said interface to anesophageal probe.
 5. The system of claim 1 further comprising a storagesystem that stores said plurality of impedance values and said pluralityof pressure values; and a user input device that generates controlsignals that cause said impedance values and said pressure values storedin said storage system to be processed by said processing system.
 6. Thesystem of claim 1 wherein said processing system is configured togenerate display data for simultaneously displaying said bolus transitand said esophagus movement as an animated display.
 7. The system ofclaim 1 wherein said processing system is further configured tosimultaneously generate a data display portion on said display deviceand generate an animated display portion on said display device.
 8. Thesystem of claim 1 wherein said processing system generates display datathat graphically depicts a swallowing operation.
 9. The system of claim1 wherein said processing system generates display data that graphicallydepicts a gastrointestinal reflux occurrence.
 10. The system of claim 1wherein said processing system generates display data from saidplurality of pressure values that illustrates muscle contraction andmuscle expansion patterns of an esophagus.
 11. The system of claim 1wherein said processing system generates display data from saidplurality of pressure values that includes a lower esophageal sphincter(LES) pressure value.
 12. The system of claim 10 wherein said musclecontraction and muscle expansion patterns illustrate a peristaltic wave.13. The system of claim 1 wherein said plurality of impedance valuescomprises a plurality of time-sampled impedance values.
 14. The systemof claim 1 wherein said plurality of pressure values comprises aplurality of time-sampled pressure values.
 15. The system of claim 5wherein said user input device generates control signals that allow auser to select a time scale for display of said display data.
 16. Thesystem of claim 1 wherein said user input device generates controlsignals that allow a user to start and stop said display data that isdisplayed on said display.